Though she's been in relationships with various men throughout the years, Olivia has never married, which leaves many wondering where her son, Noah Porter (now Noah Porter-Benson), came from. In short, he's adopted. At the end of the Season 15 finale in 2014, Olivia became the court-appointed legal guardian of a Noah, who was an orphaned baby. Initially, the agreement was for a trial period of one year with the option to apply for legal adoption after that — and that's exactly what Olivia did. At the end of Season 16, despite her demanding job and Noah's health issues, Olivia decided to adopt Noah and they've been a family ever since.

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Where did Noah initially come from, though? Good question. OK, so Noah's birth parents are the late Ellie Porter, who was a prostitute, and the late Johnny Drake, who was a sex trafficker. In 2014, when he was still a baby, Noah was discovered by Olivia along with Detective Amanda Rollins in the home of child pornographers. The discovery made headlines and was covered by the media nonstop, but still, no one ever came to claim Noah — so he was placed in foster care.

When he was in foster care, it was discovered that he was suffering from an untreated viral infection, and he was quickly removed from the home where he was staying. After that, Noah went through three more foster homes and was eventually placed back into the custody of the state. But, eventually, it was discovered that Ellie was his mother, and, wanting to get her son back, Ellie decided to get herself clean and testify against her pimp. Sadly though, just before she was due in court, Ellie snuck out of her group home to get high, and it was there that she was gang-raped and set on fire. Noah was then placed back in the state's custody until a judge granted Olivia temporary custody while she looked for Ellie's killers.

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At one point, Noah's case worker insinuated that she didn't fully trust Olivia and tried to have him removed from her home. In the end though, the judge ruled in Olivia and Noah's favor and the two have been a happy family ever since. And as we all know, Olivia has turned out to be a great mother.